Avoiding media access control padding of trigger-based physical layer convergence protocol data unit

ABSTRACT

A wireless station (STA) in a wireless local area network (WLAN) performs a method to avoid media access control (MAC) padding of a physical layer convergence protocol data unit (PPDU) (e.g., a trigger-based (TB) PPDU, etc.). The method can reduce current or power consumption by the STA, which can in turn optimize the STA and, in certain instances, the WLAN as whole. In one example, the method includes the STA receiving a trigger frame from an access point (AP). The trigger frame specifies a length of a PPDU. The method further includes the STA generating a TB PPDU based on the specifications in the trigger frame. In particular, the STA generates a PPDU that has a length that is less than the length specified by the trigger frame. The method also includes the STA transmitting the generated PPDU to the AP.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to U.S. Provisional Application No.62/955,694, filed Dec. 31, 2019, which is hereby incorporated byreference.

BACKGROUND

In the Institute of Electrical and Electronics Engineers (IEEE) 802.11axprotocol, an access point (AP) can communicate with multiple stations(STAs) simultaneously. In one scenario, the AP transmits a trigger frameto the STAB to discover data that the STAB wish to send to the AP. Eachof the STAs responds to the AP's trigger frame with a physical layerconvergence protocol data unit (PPDU) that contains the requestedinformation.

When generating a PPDU, an STA may need to pad the PPDU in order tosatisfy the length of the PPDU defined in the trigger frame. A largeportion of the padding is done on the media access control (MAC) layerby adding dummy frames to reach the defined length. PPDU lengthequalization is used to avoid or minimize potential transient eventsthat may occur when an STA stops transmitting its PPM in the middle ofan uplink (UL) transmission. These transient effects can decrease thePPDU's error vector magnitude (EVM). In addition, transmission of thepadding in a PPDU may require more resources than transmission of thedata in the PPDU. For example, the current or time associated withtransmitting the padding in the PPDU may be undesirably larger than thecurrent or time associated with transmitting data in the PPM.Furthermore, current or power consumption in the case of ULtransmission, which is subject to the AP's grouping policy, may beaffected by unpredictability and instability.

SUMMARY

A wireless station (STA) in a wireless local area network (WLAN)performs a method to avoid media access control (MAC) padding ofInstitute of Electrical and Electronics Engineers (IEEE) 802.11axtrigger-based (TB) physical layer convergence protocol data unit (PPDU).The method can reduce current consumption by the STA, which can in turnoptimize the STA and, in certain instances, the WLAN as whole. In oneexample, the method includes the STA receiving a trigger frame from anaccess point (AP). The trigger frame specifies a length of a TB PPDU.The method further includes the STA generating an TB PPDU based on thespecifications in the trigger frame. In particular, the STA generates anTB PPDU that has a length that is less than the length specified by thetrigger frame. The method also includes the STA transmitting thegenerated TB PPDU to the AP.

In another example, the method described above in the precedingparagraph may be implemented using one or more non-transitory computerreadable mediums. Additionally, the method described above in thepreceding paragraph may be implemented by an apparatus having means toperform the operations of the method.

BRIEF DESCRIPTION OF THE DRAWINGS

For a detailed description of various examples, reference will now bemade to the accompanying drawings in which:

FIG. 1 is an illustration of an example architecture of a system of anetwork.

FIGS. 2A-2B are illustrations of timing diagrams showing interactionsbetween an example access point (AP) and example wireless stations(STAs) in a system of a network designed in accordance with theInstitute of Electrical and Electronics Engineers (IEEE) 802.11axprotocol.

FIG. 3 is an illustration of an example graph highlighting a gradualdrop in gain over time that is attributable to a gradual shutdown of anexemplary wireless station (STA).

FIG. 4 is an illustration of an electronic device in accordance withsome examples.

FIG. 5 is an illustration of components of an electronic device inaccordance with some examples.

DETAILED DESCRIPTION

The examples described herein pertain to one or more devices (e.g.,wireless stations (STAs), access points (APs), etc.) configured tooperate in a network (e.g., a wireless local area network (WLAN), etc.)that is designed in accordance with a wireless protocol (e.g., theInstitute of Electrical and Electronics Engineers (IEEE) 802.11axprotocol, any other IEEE 802.11 protocol, any other suitable wirelessprotocol, any combination thereof, etc.). In one scenario, the exampleSTAs generate a trigger-based (TB) physical layer convergence protocoldata unit (PPDU) in response to receiving a trigger frame from an AP. Inthis scenario, the generated TB PPDU has a length that is shorter thanthe length specified by the trigger frame. The generated TB PPDU'sshorter length is attributable to the generated TB PPDU comprisinglittle or no padding. Consequently, the amount of current or powerassociated with transmitting the generated TB PPDU can be reduced. Morespecifically, the current or power associated with transmitting thegenerated TB PPDU is less than the current or power associated withtransmitting an TB PPDU having the length specified by the triggerframe. The current or power savings that are attributable to thegenerated TB PPDU can improve the operation of the STA and, in somescenarios, the network itself.

FIG. 1 is an illustration of an example architecture of a system 100 ofa network (e.g., a local area network (LAN), a wireless LAN (WLAN),etc.). The following description is provided for an example system 100that operates in conjunction with a wireless protocol (e.g., the IEEE802.11ax protocol, any other IEEE 802.11 protocol, any other suitablewireless protocol, any combination thereof, etc.). Notably, the examplesystem 100 is not limited to the IEEE 802.11ax protocol and may apply toother protocols or combinations or protocols that benefit from theprinciples described herein, such as current and future IEEE 802.11protocols.

As shown in FIG. 1, the system 100 includes an AP 101 coupled to anantenna array 105. The antenna array 105 shown in FIG. 1 comprises oneantenna; however, the antenna array 105 may include multiple antennae.In one example, the antenna array 105 is coupled to one or morereceivers (not shown) of the AP 101 that are capable of receiving anynumber of signals. The antenna array 105, in one example, is coupled toone or more transmitters of the AP 101 (not shown) that are capable oftransmitting any number of signals. An example antenna array 105 may becommunicatively coupled to one or more transceivers (not shown) of theAP 101 that can receive or transmit any number of signals.

The AP 101 is sometimes referred to as a wireless AP (WAP). The AP 101may be a hardware device or node on a LAN or a WLAN that allows devices(e.g., STAs 103A-103C, etc.) to connect to each other, the Internet, oranother network using a wireless standard (e.g., any one of the IEEE802.11 protocols, Bluetooth, etc.).

The system 100 also includes STAs 103A-103C, which can, among others,receive frames or packets from the AP 101 and transmit frames or packetsto the AP 101. As shown in FIG. 1, each of the STAs 103A-103C includes acorresponding antenna array 107A-107C. Each of the antenna arrays107A-107C may include one or more antennae. Each antennae array107A-107C may be communicatively coupled to one or more receivers (notshown) of a corresponding one of STAs 103A-103C that can receivesignals. In one example, each antennae 107A-107C may be communicativelycoupled to one or more transmitters (not shown) of a corresponding oneof STAs 103A-103C that can transmit signals. Each antennae 107A-107C, inone example, is communicatively coupled to one or more transceivers (notshown) of a corresponding one of STAs 103A-103C that can receive ortransmit signals. In one embodiment, each of the STAs 103A-103C is adevice that has the capability to use one or more of the IEEE 802.11protocols (e.g., IEEE 802.11ax protocol, etc.). An STA (e.g., any one ofSTAs 103A-103C, etc.) may, for example, be a laptop, a desktop personalcomputer (PC), personal digital assistant (PDA), Wi-Fi phone, a vehicle,a wearable, a tablet, or any other type of computing device that can beoperated by an end user. An STA (e.g., any one of STAs 103A-103C, etc.)may be fixed, mobile, or portable. At least one of STAs 103A-103C is adevice that contains an IEEE 802.11-conformant media access control(MAC) and a physical layer (PHY) interface to a wireless medium (WM).

As shown in FIG. 1, the AP 101 can communicate 109A through wireless orwired coupling mechanisms with the STA 103A. Similarly, the AP 101 cancommunicate 109B through wireless or wired coupling mechanisms with theSTA 103B. In the same vein, the AP 101 can communicate 109C throughwireless or wired coupling mechanisms with the STA 103C.

The system 100 may be designed in accordance with the IEEE 802.11axprotocol. In such a system, the AP 101 can utilize orthogonalfrequency-division multiple access (OFDMA), which makes it possible tosimultaneously transmit, in parallel, frames to multiple STAs (e.g.,STAs 103A-103C, etc.). One feature of OFDMA includes subdividing achannel into smaller frequency allocations, called resource units (RUs).To serve the multiple STAs 103A-103C, the AP 101 assigns at least one RUto each of the STAs 103A-103C. After the assignment of RUs, uplink (UL)and downlink (DL) communications can occur between the AP 101 and themultiple STAs 103A-103C simultaneously on the RUs.

Multi-user multiple input multiple output (MU-MIMO) is another featureof a system 100 that is designed in accordance with the IEEE 802.11axprotocol. Like OFDMA, MU-MIMO also allows for simultaneous UL and DLcommunications between the AP 101 and the STAs 103A-103C. MU-MIMOincludes using beamforming to direct signals to one or more intendedwireless devices (e.g., the AP 101, one or more of the STAs 103A-103C,etc.).

To coordinate UL OFDMA transmissions or UL MU-MIMO transmissions, the AP101 can transmit a trigger frame to the STAs 103A-103C. A trigger frameis a control frame that administers access to a WM and provides MAClayer reliability functions. More specifically, a trigger framespecifies common parameters of an upcoming UL OFDMA transmission or anupcoming UL MU-MIMO transmission (e.g., duration, guard intervals (GIs),etc.), allocates RUs for the STAs 103A-103C, and defines one or moretransmission parameters for at least one of the STAs 103A-103C. Thesetransmission parameters include a packet length, a transmit power, amodulation and coding scheme (MCS), a number of spatial streams (NSS), achannel width, a modulation scheme, an encoding scheme, a physical layerconvergence protocol data unit (PPDU) format, a bandwidth (BW), a PPDUduration, etc.

After receiving the trigger frame, the STAs 103A-103C respond in asynchronized fashion. More specifically, the STAs 103A-103C generate atrigger-based (TB) packet. The TB packet can be a TB PPDU or any otherTB packet used to respond to a trigger frame. The STAs 103A-103C furthertransmit, to the AP 101, the TB packet after a specified time intervalcalled a short interframe space (SIFS). After the AP 101 receives the TBpacket, the AP 101 generates one or more block acknowledgement (BA)frames (e.g., a BA frame for each STA 103A-103C, a multi-STA BA framefor two or more of the STAs 103A-103C, etc.). The AP 101 then transmits,to the STAs 103A-103C, the BA frame(s) after the SIFS. Subsequently, ULOFDMA transmissions or UL MU-MIMO transmissions can begin.

A trigger frame may specify a packet length for the TB packets (e.g., TBPPDUs, etc.) generated by the STAs 103A-103C. Usually, the packet lengthis the same for all the TB packets that are to be generated by the STAs103A-103C. In many scenarios, the STAs 103A-103C include differingamounts of data in each of their respective TB packets. For example, theamount of data that the STA 103A includes in its TB packet is smallerthan or larger than the amount of data that the STA 103B includes in itsTB packet. However, due to the fact that each of the TB packetsassociated with the STAs 103A-103C is to have the same length, some ofthe TB packets may need to be padded to fulfill the length requirement.This phenomenon is sometimes referred to as packet length equalization.

Padding includes filling up unused portions of a data structure (e.g., apacket, a frame, etc.) with bits, characters, and/or dummy frames.Padding may be performed at the end of the data structure to fill it upwith data. Data structures may be padded with “1” bits, blankcharacters, null characters, or dummy frames. With specific regard tothe example system 100, transmitting padded TB packets from the STAs103A-103C to the AP 101 can, in some situations, be suboptimal. Forexample, the amount of current or power associated with transmitting apadded TB packet from the STA 103A to the AP 101 may be suboptimal. Inparticular, and for this example, the amount of current or powerassociated with transmitting the padding in the padded TB packet may beundesirably larger than the amount of current or power associated withtransmitting the data portion of the padded TB packet. In such ascenario, current or power is wasted on transmitting unimportant data(e.g., padding, etc.).

Examples described herein can assist with reducing the amount of currentor power associated with transmitting a TB packet generated by an STA.In one example, an STA (e.g., any one of STAs 103A-103C, etc.) has datathat will not fill up a TB packet (e.g., a TB PPDU, etc.) whose lengthis specified in a trigger frame received by the STA. In this example,the STA generates a TB packet with a length that is less than the lengthspecified by the trigger frame. More specifically, the STA generates aTB packet with little or no padding. The example TB packet willsometimes be referred to herein as a shortened TB packet.

Given that there is little to no padding in a shortened TB packet,mostly or only relevant or required data is included in the shortened TBpacket. Minimizing or eliminating the padding in a TB packet results inreducing the amount of current or power associated with transmitting theTB packet. That is, transmitting a shortened TB packet (which has alength that is less than a length specified by a trigger frame) avoidsone or more of the shortcomings described above. For one example, theamount of current or power associated with transmitting the data portionof a shortened TB packet will be higher than the current or powerassociated with transmitting the padding of the shortened TB packet (ifthe shortened TB packet includes padding). For another example, and withregard to a shortened TB packet that lacks padding, there will be nocurrent or power dedicated to transmitting padding. In both of thepreceding examples, most or all of the current or power associated withtransmitting the shortened TB packet is dedicated to transmitting thedata portion of the shortened TB packet. In this way, little or nocurrent or power is dedicated to transferring padding. Given thatcurrent or power is saved by using the shortened TB packet (instead of a“full length” TB packet), the transmitting STA's operation or thefunctioning of the system 100 as a whole may be improved.

FIGS. 2A-2B are illustrations of timing diagrams showing interactionsbetween an example access point (AP) 201 and example wireless stations(STAs) 203A-203C in a system 200 of a network designed in accordancewith the IEEE 802.11ax protocol. The system 200 is similar to or thesame as the system 100 described above in connection with FIG. 1. Asshown in FIGS. 2A-2B, the system 200 includes an AP 201 and STAs203A-203C. The AP 201 is similar to the AP 101 described above inconnection with FIG. 1.

In each of FIGS. 2A-2B, data exchanges between the AP 201 and the STAs203A-203C are with regard to time, which is represented by thehorizontal axis 243. Time, as depicted by the horizontal axis 243,increases in the right direction. Thus, frames and packets are exchangedat specific times (e.g, t₁, t₂, t₃, short interframe space (SIFS) 245,etc.).

With regard now to FIG. 2A, the AP 201 generates a trigger frame 231.Trigger frames are described above in connection with FIG. 1. Next, attime t₁, the AP 201 transmits the trigger frame 231 to the STAs203A-203C during a time frame t₁.

Following receipt of the trigger frame 231, each of the STAs 203A-203Cprocesses the trigger frame 231 and generates a TB packet. Morespecifically, the STA 203A processes the trigger frame 231 and generatesa TB packet 237, the STA 203B processes the trigger frame 231 andgenerates a TB packet 239, and the STA 203A processes the trigger frame231 and generates a TB packet 241. Each of the TB packets 237, 239, and241 can be a TB PPDU or any other TB packet used for responding to atrigger frame (e.g., trigger frame 231, etc.).

After a SIFS 245A has elapsed, each of the STAs 203A-203C transmits itsrespective one of the TB packets 237, 239, and 241 to the AP 201 duringa time frame t₂. The AP 201 generates a BA 233 in response to receivingthe TB packets 237, 239, and 241. After a SIFS 245B has elapsed, the AP201 transmits the BA 233 to the STAs 203A-203C during a time frame t₃.After the STAs 203A-203C receive the BA 233, UL OFDMA transmissions orUL MU-MIMO transmissions can begin. In one example, the SIFS 245A-245Bhave the same duration, which is predetermined.

Each of the TB packets 237, 239, and 241 can be a TB PPDU. In somescenarios, a TB PPDU includes a legacy preamble, a high efficiency (HE)preamble, and a payload, which is sometimes referred to herein as data.In other scenarios, the TB PPDU further includes padding. As shown inFIG. 2A, the TB PPDU 237 includes a legacy preamble 205, an HE preamble207, data 209, and padding 211. Furthermore, and as shown in FIG. 2A,the TB PPDU 239 includes a legacy preamble 213, an HE preamble 215, data217, and no padding. Additionally, and as shown in FIG. 2A, the TB PPDU241 includes a legacy preamble 221, an HE preamble 223, data 225, and nopadding/data.

A legacy preamble (e.g., any one of the legacy preambles 205, 213, and221, etc.) enables a TB PPDU to be decoded by legacy devices (e.g.,devices that are not designed to work with the IEEE 802.11ax protocol,etc.). In other words, the legacy preamble is included in the TB PPDUfor backward compatibility. The legacy preamble includes: (i) a legacyshort training field (L-STF), which is sometimes referred to as anon-high throughput (HT) short training field; (ii) a legacy trainingfield (L-LTF), which is sometimes referred to as a non-HT trainingfield; and (iii) a legacy signal field (L-SIG), which is sometimesreferred to as a non-HT signal field.

An HE preamble (e.g., HE preamble 207, HE preamble 215, HE preamble 223,etc.) can only be decoded by devices that are designed to work with theIEEE 802.11ax protocol. An HE preamble includes: (i) a repeated legacysignal field (RL-SIG), which is sometimes referred to as a repeatednon-HT signal field; (ii) an HE signal A field (HE-SIG-A); (iii) an HEsignal B field (HE-SIG-B); (iv) an HE short training field (HT-STF); and(v) an HE long training field (HE-LTF).

A TB PPDU also includes a payload (e.g., data 209, data 217, data 225,etc.). Such data may include a service field, a physical layer servicedata unit (PSDU), and PPDU tail bits. A part of the bits of the servicefield may be used for synchronization at a receiver. The PSDUcorresponds to a MAC protocol data unit (PDU) defined at the MAC layerand may include data generated/used in a higher layer. The PPDU tailbits may be used to return an encoder to a zero state.

Usually, the legacy preambles (e.g., legacy preamble 205, legacypreamble 213, legacy preamble 221, etc.) have a predetermined size, andas a result, will require a predetermined amount of time (e.g., lengthof time, etc.) to be transmitted to the AP 201. Additionally, the HEpreambles (e.g., HE preamble 207, HE preamble 215, HE preamble 223,etc.) have a predetermined size, and as a result, will require apredetermined amount of time (e.g., length of time, etc.) to betransmitted to the AP 201. The payloads (e.g., data 209, data 217, data225, etc.), however, may have differing sizes from each other, and as aresult, will require differing amounts of time (e.g., lengths of time,etc.) to be transmitted to the AP 201. For example, and as shown in FIG.2A, the data 225 is smaller than the data 209, which is smaller than thedata 217. Consequently, and for this example, the lengths of timeassociated with transmitting the data 209, data 217, and data 225 willvary. In spite of these differences, each of the TB PPDUs 237, 239, and241 has a common information length 235 that is specified by the triggerframe 231. That is, each of the STAs 203A-C is required to communicateits respective one of the TB PPDUs 237, 239, and 241 within a specifictime frame (t₂) that is based on the common information length 235 setforth in the trigger frame 231. In such a scenario, one or more of theSTAs 203A-203C may employ padding to ensure that its TB PPDU conforms tothe length specified by the trigger frame 231. For example, and withregard to FIG. 2A, the STA 203A generates a TB PPDU 237 that includes alegacy preamble 205, an HE preamble 207, data 209, and padding 211. Inthis example, the data 209 lacks a length that satisfies the commoninformation length 235. Thus, the STA 203A pads the TB PPDU 237 toensure that the TB PPDU 237 conforms to the length specified by thetrigger frame 231.

It is not always the case that an STA (e.g., any one of STAs 203A-203C,etc.) employs padding. For example, and with regard to FIG. 2A, the STA203B generates a TB PPDU 239 that includes a legacy preamble 213, an HEpreamble 215, and data 217. In this example, the data 217 has a lengththat satisfies the common information length 235. Thus, the STA 203Bdoes not pad the TB PPDU 239.

With specific regard to the system 200 set forth in FIG. 2A,transmitting the padded TB PPDU 235 from the STA 103A to the AP 201 can,in some situations, be suboptimal. For example, the amount of current orpower associated with transmitting the padded TB PPDU 235 from the STA103A to the AP 201 may be suboptimal. In particular, and for thisexample, the amount of current or power associated with transmitting thepadding 211 in the padded TB PPDU 235 may be higher than the amount ofcurrent or power associated with transmitting the data 209 in the paddedTB PPDU 235. In such a scenario, current or power is wasted ontransmitting unimportant data (e.g., padding 211, etc.).

Examples described herein can assist with reducing the amount of currentor power associated with transmitting a TB packet generated by an STA.In one example, and with regard to FIG. 2A, the STA 203C has data 225that will not fill up the TB PPDU 241, whose length is specified in thetrigger frame 231 received by the STA 203C. In this example, the STA203C generates a TB PPDU 241 with a length Li that is less than thecommon information length 235 specified by the trigger frame 231. Inparticular, the STA 203C generates a TB PPDU 241 with no padding. Thisexample TB PPDU 241 will sometimes be referred to herein as a shortenedTB PPDU 241.

Given that there is no padding in the shortened TB PPDU 241, onlyrelevant or required data 225 is included in the shortened TB PPDU 241.Eliminating the padding in the TB PPDU 241 results in reducing theamount of current or power associated with transmitting the TB PPDU 241.That is, transmitting a shortened TB PPDU 241 (which has a length L₁that is less than a length 235 specified by the trigger frame 231)avoids one or more of the shortcomings described above. For example, andwith regard to the shortened TB PPDU 241, there will be no current orpower dedicated to transmitting padding. Thus, most or all of thecurrent or power associated with transmitting the shortened TB PPDU 241is directed to transmitting the data 225. Given that current or power issaved by using the shortened TB PPDU (instead of a “full length” TBPPDU, such as the TB PPDU 237), the transmitting STA 203C's operation orthe functioning of the system 200 as a whole may be improved.

Referring now to FIG. 2B, another example of the system 200 is shown.The system 200 set forth in FIG. 2B is similar to the system 200 setforth in FIG. 2A, with the exception that the STA 203C in FIG. 2Bgenerates and transmits a TB PPDU 249 to the AP 201. The example TB PPDU249 includes a legacy preamble 221, an HE preamble 223, data 225, andpadding 247. The TB PPDU 249 is one example of a TB packet that canassist with reducing the amount of current or power associated withtransmitting the TB packet generated by an STA. In one example, and withregard to FIG. 2B, the STA 203C has data 225 that will not fill up theTB PPDU 247, whose length is specified in the trigger frame 231 receivedby the STA 203C. In this example, the STA 203C generates a TB PPDU 249with a length L₂ that is less than the common information length 235specified by the trigger frame 231. In particular, the STA 203Cgenerates a TB PPDU 249 with padding 247 that does not fill up theentire length, as specified by the trigger frame 231, of the TB PPDU249. This example TB PPDU 249 will sometimes be referred to herein as ashortened TB PPDU 249.

Given that there is only a small amount of padding 247 in the shortenedTB PPDU 249, only relevant or required data 225 and a small amount ofunimportant data (e.g., padding 247, etc.) is included in the shortenedTB PPDU 249. Minimizing the padding in the TB PPDU 249 results inreducing the amount of current or power associated with transmitting theTB PPDU 249. That is, transmitting a shortened TB PPDU 249 (which has alength L₂ that is less than a length 235 specified by the trigger frame231) avoids one or more of the shortcomings described above. Forexample, and with regard to the shortened TB PPDU 249, the current orpower dedicated to transmitting padding 247 will be less than thecurrent or power dedicated to transmitting the data 225. Thus, a largerproportion of the current or power associated with transmitting theshortened TB PPDU 249 is dedicated to transmitting the data 225 and asmaller proportion of the current or power associated with transmittingthe shortened TB PPDU 249 is dedicated to transmitting unimportant data(e.g., padding 247, etc.). Given that current or power is saved by usingthe shortened TB PPDU 249 (instead of a “full length” TB PPDU, such asthe TB PPDU 237), the STA 203C's operation or the functioning of thesystem 200 as a whole may be improved.

In FIGS. 2A-2B, the STA 203C completes transmission of the shortened TBPPDU (e.g., TB PPDU 241, TB PPDU 249, etc.) prior to the end of the timeframe t₂. In some scenarios, after the STA 203C completes thetransmission of the shortened TB PPDU (e.g., TB PPDU 241, TB PPDU 249,etc.), the STA 203C shuts down. Consequently, the STA 203C will shutdown before any one of the STAs 203A-203B shuts down. In many scenarios,the STA 203C may shut down abruptly. The STA 203C's early and abruptshutdown may affect the operation of the STAs 203A-203B. Specifically,the STA 203C's early and abrupt shutdown may result in transient eventsthat negatively impact the operation of the STAs 203A-203B. To avoid thecreation of transient events, the STA 203C may, in one example, bedesigned to gradually shut down 251 after transmitting the shortened TBPPDU (e.g., TB PPDU 241, TB PPDU 249, etc.) to the AP 201. In oneexample, and as shown in each of FIGS. 2A-2B, the STA 203C graduallyshuts down 251 radio frequency (RF) power associated with transmittingthe shortened TB PPDU (e.g., TB PPDU 241, TB PPDU 249, etc.) followingtransmission of the data 225 in the shortened TB PPDU. FIG. 3, which isdescribed below, provides additional details about gradually shuttingdown an STA that transmits a shortened TB PPDU to an AP.

FIG. 3 is an illustration of an example graph 300 highlighting a gradualdrop in gain over time that is attributable to a gradual shutdown of anexample wireless station (STA). The graph 300 includes a vertical axis305 that represents the gain in current (or power) associated with theexample STA and a horizontal axis 307 that represents the timeassociated with shutting down the example STA after it completestransmission of a TB packet (e.g., a TB PPDU, a shortened TB PPDU,etc.).

As explained above in FIGS. 1-2B, an STA (e.g., the STA 203C describedabove in connection with FIGS. 2A-2B, etc.) that transmits a shortenedTB PPDU (e.g., TB PPDU 241, TB PPDU 249, etc.) to an AP (e.g., AP 201,etc.) will complete its transmission prior to a length of time specifiedby a trigger frame (e.g., trigger frame 231, etc.). Usually, the STAthat transmits the shortened TB PPDU shuts down abruptly aftertransmitting the shortened TB PPDU. This abrupt shutdown creates sharpdrop in gain, as shown by the curve 303 set forth in FIG. 3.Conceptually, the sharp drop in gain represented by the curve 303 may belikened to an ideal brick wall response 303. The sharp drop in gain maycreate transient events that affect the operation of other STAs that areassociated with the STA that transmitted the shortened TB PPDU.

In one example, the STA that transmits the shortened TB PPDU is designedto gradually shutdown after transmitting the shortened TB PPDU to theAP. This gradual shutdown creates a gradual drop in gain, as representedby the curve 301 set forth in the graph 300. This gradual drop in gainminimizes or eliminates the occurrence of transient events that mayaffect the operation of other STAs that are associated with the STA thattransmitted the shortened TB PPDU.

FIG. 4 is an illustration of an electronic device 400 in accordance withsome examples. The electronic device 400 may implement any or all of abase station or an AP (e.g., AP 101, AP 201, etc.) or an STA (e.g., anyone of STAs 103A-103C, any one of STAs 203A-203C, etc.) and/or any otherelement/device discussed herein. The electronic device 400 may includeone or more of application circuitry 405, baseband circuitry 410, one ormore radio front end modules 415, memory circuitry 420, power managementintegrated circuitry (PMIC) 425, power circuitry 430, network controllercircuitry 435, network interface connector 440, satellite positioningcircuitry 445, and user interface 450. In some examples, the electronicdevice 400 may include additional elements such as, for example,memory/storage, display, camera, sensor, or input/output (I/O)interface. In other examples, the components described below may beincluded in more than one device. That is, the electronic device 400 maybe spread across multiple devices.

As used herein, the term “circuitry” may refer to, is part of, orincludes hardware components such as an electronic circuit, a logiccircuit, a processor (shared, dedicated, or group) and/or memory(shared, dedicated, or group), an application specific integratedcircuit (ASIC), a field-programmable device (FPD) (e.g., afield-programmable gate array (FPGA), a programmable logic device (PLD),a complex PLD (CPLD), a high-capacity PLD (HCPLD), a structured ASIC, ora programmable System on Chip (SoC)), digital signal processors (DSPs),etc., that are configured to provide the described functionality. Insome examples, the circuitry may execute one or more software orfirmware programs to provide at least some of the describedfunctionality. In addition, the term “circuitry” may also refer to acombination of one or more hardware elements (or a combination ofcircuits used in an electrical or electronic system) with the programcode used to carry out the functionality of that program code. In theseexamples, the combination of hardware elements and program code may bereferred to as a particular type of circuitry.

The terms “application circuitry” and/or “baseband circuitry” may beconsidered synonymous to, and may be referred to as, “processorcircuitry.” As used herein, the term “processor circuitry” may refer to,is part of, or includes circuitry capable of sequentially andautomatically carrying out a sequence of arithmetic or logicaloperations, or recording, storing, and/or transferring digital data. Theterm “processor circuitry” may refer to one or more applicationprocessors, one or more baseband processors, a physical centralprocessing unit (CPU), a single-core processor, a dual-core processor, atriple-core processor, a quad-core processor, and/or any other devicecapable of executing or otherwise operating computer-executableinstructions, such as program code, software modules, and/or functionalprocesses.

Furthermore, the term “network element” may describe a physical orvirtualized equipment used to provide wired or wireless communicationnetwork services. The term “network element” may be consideredsynonymous to and/or referred to as a networked computer, networkinghardware, network equipment, network node, router, switch, hub, bridge,radio network controller, AP (e.g., AP 101, AP 201, etc.), gateway,server, virtualized virtual network function (VNF), network functionsvirtualization infrastructure (NFVI), and/or the like.

Application circuitry 405 may include one or more central processingunit (CPU) cores and one or more of cache memory, low drop-out voltageregulators (LDOs), interrupt controllers, serial interfaces such as SPI,I2C or universal programmable serial interface module, real time clock(RTC), timer-counters including interval and watchdog timers, generalpurpose input/output (I/O or IO), memory card controllers such as SecureDigital (SD) MultiMediaCard (MMC) or similar, Universal Serial Bus (USB)interfaces, Mobile Industry Processor Interface (MIPI) interfaces andJoint Test Access Group (JTAG) test access ports. In some examples, theelectronic device 400 may not utilize application circuitry 405, andinstead may include a special-purpose processor/controller to processinternet protocol (IP) data received from a network (e.g., a networkdesigned in accordance with the 802.11ax protocol, a network designed inaccordance with any of the other 802.11 protocols, etc.).

Additionally or alternatively, application circuitry 405 may includecircuitry such as, but not limited to, one or more a field-programmabledevices (FPDs) such as field-programmable gate arrays (FPGAs) and thelike; programmable logic devices (PLDs) such as complex PLDs (CPLDs),high-capacity PLDs (HCPLDs), and the like; ASICs such as structuredASICs and the like; programmable SoCs (PSoCs); and the like. In suchexamples, the circuitry of application circuitry 405 may comprise logicblocks or logic fabric, and other interconnected resources that may beprogrammed to perform various functions, such as the procedures,methods, functions, etc. of the various examples discussed herein (e.g.,generation of a shortened TB PPDU as described above in connection withFIGS. 1-3, etc.). In such examples, the circuitry of applicationcircuitry 405 may include memory cells (e.g., erasable programmableread-only memory (EPROM), electrically erasable programmable read-onlymemory (EEPROM), flash memory, static memory (e.g., static random accessmemory (SRAM), anti-fuses, etc.)) used to store logic blocks, logicfabric, data, etc. in look-up-tables (LUTs) and the like.

The baseband circuitry 410 may be implemented, for example, as asolder-down substrate including one or more integrated circuits (ICs), asingle packaged IC soldered to a main circuit board or a multi-chipmodule containing two or more ICs. Although not shown, basebandcircuitry 410 may comprise one or more digital baseband systems, whichmay be coupled via an interconnect subsystem to a central processingunit (CPU) subsystem, an audio subsystem, and an interface subsystem.The digital baseband subsystems may also be coupled to a digitalbaseband interface and a mixed-signal baseband subsystem via anotherinterconnect subsystem. Each of the interconnect subsystems may includea bus system, point-to-point connections, network-on-chip (NOC)structures, and/or some other suitable bus or interconnect technology.The audio subsystem may include digital signal processing circuitry,buffer memory, program memory, speech processing accelerator circuitry,data converter circuitry such as analog-to-digital and digital-to-analogconverter circuitry, analog circuitry including one or more ofamplifiers and filters, and/or other like components. In some examples,the baseband circuitry 410 may include protocol processing circuitrywith one or more instances of control circuitry (not shown) to providecontrol functions for the digital baseband circuitry and/or radiofrequency circuitry (e.g., the radio front end modules 415).

User interface circuitry 450 may include one or more user interfacesdesigned to enable user interaction with the electronic device 400 orperipheral component interfaces designed to enable peripheral componentinteraction with the system 400. User interfaces may include, but arenot limited to, one or more physical or virtual buttons (e.g., a resetbutton), one or more indicators (e.g., light emitting diodes (LEDs)), aphysical keyboard or keypad, a mouse, a touchpad, a touchscreen,speakers or other audio emitting devices, microphones, a printer, ascanner, a headset, a display screen or display device, etc. Peripheralcomponent interfaces may include, but are not limited to, a nonvolatilememory port, a universal serial bus (USB) port, an audio jack, a powersupply interface, etc.

The radio front end modules (RFEMs) 415 may comprise a millimeter waveRFEM and one or more sub-millimeter wave radio frequency integratedcircuits (RFICs). In some implementations, the one or moresub-millimeter wave RFICs may be physically separated from themillimeter wave RFEM. The RFICs may include connections to one or moreantennas or antenna arrays, and the RFEM may be connected to multipleantennas. In alternative implementations, both millimeter wave andsub-millimeter wave radio functions may be implemented in the samephysical radio front end module 415. The RFEMs 415 may incorporate bothmillimeter wave antennas and sub-millimeter wave antennas. In oneexample, one or more of the RFEMs 415 transmits a shortened TB PPDUgenerated by the application circuitry 405 to an AP (e.g., AP 101, AP201, etc.). Generating and transmitting a shortened TB PPDU is describedabove in connection with FIGS. 1-3.

The memory circuitry 420 may include one or more of volatile memoryincluding dynamic random access memory (DRAM) and/or synchronous dynamicrandom access memory (SDRAM), and nonvolatile memory (NVM) includinghigh-speed electrically erasable memory (commonly referred to as Flashmemory), phase change random access memory (PRAM), magnetoresistiverandom access memory (MRAM), etc. Memory circuitry 420 may beimplemented as one or more of solder down packaged integrated circuits,socketed memory modules and plug-in memory cards.

The PMIC 425 may include voltage regulators, surge protectors, poweralarm detection circuitry, and one or more backup power sources such asa battery or capacitor. The power alarm detection circuitry may detectone or more of brown out (under-voltage) and surge (over-voltage)conditions. The power circuitry 430 may provide for electrical powerdrawn from a network cable to provide both power supply and dataconnectivity to the electronic device 400 using a single cable.

The network controller circuitry 435 may provide connectivity to anetwork (e.g., a network designed in accordance with the 802.11axprotocol, a network designed in accordance with any one of the 802.11protocols, etc.) using a standard network interface protocol such asEthernet, Ethernet over GRE Tunnels, Ethernet over Multiprotocol LabelSwitching (MPLS), or some other suitable protocol. Network connectivitymay be provided to/from the electronic device 400 via network interfaceconnector 440 using a physical connection, which may be electrical(commonly referred to as a “copper interconnect”), optical, or wireless.The network controller circuitry 435 may include one or more dedicatedprocessors and/or FPGAs to communicate using one or more of theaforementioned protocols. In some implementations, the networkcontroller circuitry 435 may include multiple controllers to provideconnectivity to other networks using the same or different protocols.

The positioning circuitry 445 may include circuitry to receive anddecode signals transmitted by one or more navigation satelliteconstellations of a global navigation satellite system (GNSS). Examplesof navigation satellite constellations (or GNSS) may include UnitedStates' Global Positioning System (GPS), Russia's Global NavigationSystem (GLONASS), the European Union's Galileo system, China's BeiDouNavigation Satellite System, a regional navigation system or GNSSaugmentation system (e.g., Navigation with Indian Constellation (NAVIC),Japan's Quasi-Zenith Satellite System (QZSS), France's DopplerOrbitography and Radio-positioning Integrated by Satellite (DORIS),etc.), or the like. The positioning circuitry 545 may comprise varioushardware elements (e.g., including hardware devices such as switches,filters, amplifiers, antenna elements, and the like to facilitateover-the-air (OTA) communications) to communicate with components of apositioning network, such as navigation satellite constellation nodes.

Nodes or satellites of the navigation satellite constellation(s) (GNSSnodes) may provide positioning services by continuously transmitting orbroadcasting GNSS signals along a line of sight, which may be used byGNSS receivers (e.g., positioning circuitry 445 and/or positioningcircuitry implemented by STAs (e.g., any one of STAs 103A-103C, any oneof STAs 203A-203C, or the like) to determine their GNSS position. TheGNSS signals may include a pseudorandom code (e.g., a sequence of onesand zeros) that is known to the GNSS receiver and a message thatincludes a time of transmission (ToT) of a code epoch (e.g., a definedpoint in the pseudorandom code sequence) and the GNSS node position atthe ToT. The GNSS receivers may monitor/measure the GNSS signalstransmitted/broadcasted by a plurality of GNSS nodes (e.g., four or moresatellites) and solve various equations to determine a correspondingGNSS position (e.g., a spatial coordinate). The GNSS receivers alsoimplement clocks that are typically less stable and less precise thanthe atomic clocks of the GNSS nodes, and the GNSS receivers may use themeasured GNSS signals to determine the GNSS receivers' deviation fromtrue time (e.g., an offset of the GNSS receiver clock relative to theGNSS node time). In some examples, the positioning circuitry 445 mayinclude a Micro-Technology for Positioning, Navigation, and Timing(Micro-PNT) integrated circuit (IC) that uses a master timing clock toperform position tracking/estimation without GNSS assistance.

The GNSS receivers may measure the time of arrivals (ToAs) of the GNSSsignals from the plurality of GNSS nodes according to its own clock. TheGNSS receivers may determine time of flight (ToF) values for eachreceived GNSS signal from the ToAs and the ToTs, and then may determine,from the ToFs, a three-dimensional (3D) position and clock deviation.The 3D position may then be converted into a latitude, longitude andaltitude. The positioning circuitry 445 may provide data to applicationcircuitry 405 that may include one or more of position data or timedata. Application circuitry 405 may use the time data to synchronizeoperations with other radio base stations (e.g., AP 101, AP 201, etc.).

The components shown in FIG. 4 may communicate with one another usinginterface circuitry. As used herein, the term “interface circuitry” mayrefer to, is part of, or includes circuitry providing for the exchangeof information between two or more components or devices. The term“interface circuitry” may refer to one or more hardware interfaces, forexample, buses, input/output (I/O) interfaces, peripheral componentinterfaces, network interface cards, and/or the like. Any suitable bustechnology may be used in various implementations, which may include anynumber of technologies, including industry standard architecture (ISA),extended ISA (EISA), peripheral component interconnect (PCI), peripheralcomponent interconnect extended (PCIx), PCI express (PCIe), or anynumber of other technologies. The bus may be a proprietary bus, forexample, used in a SoC based system. Other bus systems may be included,such as an I2C interface, an SPI interface, point to point interfaces,and a power bus, among others.

FIG. 5 is a block diagram illustrating components, according to someexamples, able to read instructions from a machine-readable orcomputer-readable medium (e.g., a non-transitory machine-readablestorage medium) and perform any one or more of the methodologies ortechniques discussed herein. Specifically, FIG. 5 shows a diagrammaticrepresentation of hardware resources 500 including one or moreprocessors (or processor cores) 510, one or more memory/storage devices520, and one or more communication resources 530, each of which may becommunicatively coupled via a bus 540. As used herein, the term“computing resource,” “hardware resource,” etc., may refer to a physicalor virtual device, a physical or virtual component within a computingenvironment, and/or a physical or virtual component within a particulardevice, such as computer devices, mechanical devices, memory space,processor/CPU time and/or processor/CPU usage, processor and acceleratorloads, hardware time or usage, electrical power, input/outputoperations, ports or network sockets, channel/link allocation,throughput, memory usage, storage, network, database and applications,and/or the like. For examples where node virtualization (e.g., NFV,etc.) is utilized, a hypervisor 502 may be executed to provide anexecution environment for one or more network slices/sub-slices toutilize the hardware resources 500. A “virtualized resource” may referto compute, storage, and/or network resources provided by virtualizationinfrastructure to an application, device, system, etc.

The processors 510 (e.g., a central processing unit (CPU), a reducedinstruction set computing (RISC) processor, a complex instruction setcomputing (CISC) processor, a graphics processing unit (GPU), a digitalsignal processor (DSP) such as a baseband processor, an applicationspecific integrated circuit (ASIC), a radio-frequency integrated circuit(RFIC), another processor, or any suitable combination thereof) mayinclude, for example, a processor 512 and a processor 514.

The memory/storage devices 520 may include main memory, disk storage, orany suitable combination thereof. The memory/storage devices 520 mayinclude, but are not limited to, any type of volatile or nonvolatilememory such as dynamic random access memory (DRAM), static random accessmemory (SRAM), erasable programmable read-only memory (EPROM),electrically erasable programmable read-only memory (EEPROM), Flashmemory, solid-state storage, etc.

The communication resources 530 may include interconnection or networkinterface components or other suitable devices to communicate with oneor more peripheral devices 504 or one or more databases 506 via anetwork 508. For example, the communication resources 530 may includewired communication components (e.g., for coupling via a universalserial bus (USB)), cellular communication components, NFC components,Bluetooth® components (e.g., Bluetooth® Low Energy), Wi-Fi® components,and other communication components. As used herein, the term “networkresource” or “communication resource” may refer to computing resourcesthat are accessible by computer devices via a communications network.The term “system resources” may refer to any kind of shared entities toprovide services, and may include computing and/or network resources.System resources may be considered as a set of coherent functions,network data objects or services, accessible through a server where suchsystem resources reside on a single host or multiple hosts and areclearly identifiable.

Instructions 550 may comprise software, a program, an application, anapplet, an app, or other executable code for causing at least any of theprocessors 510 to perform any one or more of the methodologies ortechniques discussed herein. For example, the instructions 550 maycomprise executable code that enables generation and transmission of ashortened TB PPDU, as described above in connection with FIGS. 1-3. Theinstructions 550 may reside, completely or partially, within at leastone of the processors 510 (e.g., within the processor's cache memory),the memory/storage devices 520, or any suitable combination thereof.Furthermore, any portion of the instructions 550 may be transferred tothe hardware resources 500 from any combination of the peripheraldevices 504 or the databases 506. Accordingly, the memory of processors510, the memory/storage devices 520, the peripheral devices 504, and thedatabases 506 are examples of computer-readable and machine-readablemedia.

At least one of the components set forth in one or more of the precedingfigures may be configured to perform one or more operations, techniques,processes, and/or methods as set forth in the examples discussed herein.For example, the baseband circuitry as described above in connectionwith one or more of the preceding figures may be configured to operatein accordance with one or more of the examples discussed herein. Foranother example, circuitry associated with an STA, an AP, networkelement, etc. as described above in connection with one or more of thepreceding figures may be configured to operate in accordance with one ormore of the examples discussed herein.

In this description, the term “couple” or “couples” means either anindirect or direct wired or wireless connection. Thus, if a first devicecouples to a second device, that connection may be through a directconnection or through an indirect connection via other devices andconnections. The recitation “based on” means “based at least in parton.” Therefore, if X is based on Y, X may be a function of Y and anynumber of other factors. Furthermore, the use of “A or B,” “A and/or B,”“A and B,” “at least one of A or B,” “at least one of A and B,” “A/B,”or “one or more of A and B” is intended to mean A alone, B alone, or Aand B together.

Modifications are possible in the described examples, and other examplesare possible, within the scope of the claims.

What is claimed is:
 1. A method, comprising: receiving, by the wirelessstation (STA), a trigger frame, the trigger frame specifying a length ofa trigger-based (TB) physical layer convergence protocol data unit(PPDU); generating, by the STA, the TB PPDU, wherein a length of thegenerated TB PPDU is less than the specified length in the triggerframe; and transmitting, by the STA, the generated TB PPDU.
 2. Themethod of claim 1, further comprising: reducing, by the STA, powerassociated with transmitting the generated TB PPDU in response tocompleting transmission of the generated TB PPDU.
 3. The method of claim1, further comprising: receiving, by the STA, a block acknowledgement inresponse to completing transmission of the generated TB PPDU.
 4. Themethod of claim 3, further comprising: refraining, by the STA, fromtransmitting any data in response to completing transmission of the TBPPDU.
 5. The method of claim 4, wherein refraining, by the STA, fromtransmitting any data in response to completing transmission of the TBPPDU comprises: refraining, by the STA, from transmitting any data priorto receiving the block acknowledgment.
 6. The method of claim 1, whereingenerating the TB PPDU comprises: padding the TB PPDU.
 7. The method ofclaim 1, wherein the generated TB PPDU comprises: a legacy preamble; ahigh efficiency (HE) preamble; and data.
 8. An apparatus, comprising:communication circuitry configured to transmit and receive data; andprocessing circuitry coupled to the communication circuitry andconfigured to: receive, via the communication circuitry, a triggerframe, the trigger frame specifying a length of a trigger-based (TB)physical layer convergence protocol data unit (PPDU); generate the TBPPDU, wherein a length of the generated TB PPDU is less than thespecified length in the trigger frame; and transmit, via thecommunication circuitry, the generated TB PPDU.
 9. The apparatus ofclaim 8, wherein the processing circuitry is further configured to:reduce power associated with transmitting, via the communicationcircuitry, the generated TB PPDU in response to completing transmissionof the generated TB PPDU via the communication circuitry.
 10. Theapparatus of claim 8, wherein the processing circuitry is furtherconfigured to: receive, via the communication circuitry, a blockacknowledgement in response to completing transmission of the generatedTB PPDU via the communication circuitry.
 11. The apparatus of claim 10,wherein the processing circuitry is further configured to: refrain fromtransmitting, via the communication circuitry, any data in response tocompleting transmission of the generated TB PPDU via the communicationcircuitry.
 12. The apparatus of claim 11, wherein the processingcircuitry being configured to refrain from transmitting, via thecommunication circuitry, any data in response to completing transmissionof the generated TB PPDU via the communication circuitry comprises theprocessing circuitry being configured to: refrain from transmitting, viathe communication circuitry, any data prior to receiving, via thecommunication circuitry, the block acknowledgment.
 13. The apparatus ofclaim 8, wherein the processing circuitry being configured to generatethe TB PPDU comprises the processing circuitry being configured to: padthe TB PPDU.
 14. The apparatus of claim 8, wherein the generated TB PPDUcomprises: a legacy preamble; A high efficiency (HE) preamble; and data.15. One or more non-transitory computer readable mediums comprisinginstructions executable by one or more processors to cause a wirelessstation (STA) to: receive a trigger frame, the trigger frame specifyinga length of a trigger-based (TB) physical layer convergence protocoldata unit (PPDU); generate the TB PPDU, wherein a length of thegenerated TB PPDU is less than the specified length in the triggerframe; and transmit the generated TB PPDU.
 16. The one or morenon-transitory computer readable mediums of claim 15, further comprisinginstructions executable by the one or more processors to cause the STAto: reduce power associated with transmitting the generated TB PPDU inresponse to completing transmission of the generated TB PPDU.
 17. Theone or more non-transitory computer readable mediums of claim 15,further comprising instructions executable by the one or more processorsto cause the STA to: receive a block acknowledgement in response tocompleting transmission of the generated TB PPDU.
 18. The one or morenon-transitory computer readable mediums of claim 17, further comprisinginstructions executable by the one or more processors to cause the STAto: refrain from transmitting any data in response to completingtransmission of the generated TB PPDU.
 19. The one or morenon-transitory computer readable mediums of claim 18, wherein theinstructions that are executable by the one or more processors to causethe STA to refrain from transmitting any data in response to completingtransmission of the generated TB PPDU comprise instructions that areexecutable by the one or more processors to cause the STA to: refrainfrom transmitting any data prior to receiving the block acknowledgment.20. The one or more non-transitory computer readable mediums of claim15, wherein the instructions that are executable by the one or moreprocessors to cause the STA to generate the TB PPDU compriseinstructions that are executable by the one or more processors to causethe STA to: pad the TB PPDU.